What do women find attractive about a man's smell?

If you've ever been guilty of inching closer to a stranger because she smells good, you'll be glad to know there's plenty of science behind the desire to get a whiff. So, what do women find so attractive about a man's smell? Well, it has more to do with pheromones than expensive cologne (although we're pretty sure the latter doesn't hurt).

Pheromones are odorless chemical compounds emitted not only by men, but also by women -- and a host of animals and insects. In fact, pheromones are all part of nature's mating game, intended to create sexual attraction on a purely physical level. This probably explains why cologne manufacturers and advertising firms spend billions of dollars convincing us that smelling better makes us more popular with the opposite sex. But when it comes to the types of smells women find attractive in men, there are some surprising candidates, including citrus, baby powder and Good & Plenty candies. And, unlike men who rarely seem put off by odors, women are less aroused when the scent of cherries or charcoal barbecue smoke lingers in the air [source: Johnson].

Guys, you should also know women don't particularly appreciate the scent of stale sweat, either. Remember what we said about pheromones being odorless? If you want us to get close enough to pick up on your pheromones, plan on being sweat-free -- or newly sweaty, at least. Women have more sensitive smell receptors than men and prefer certain scents only when they're fresh, such as androstenol, which is emitted when sweat and oxygen intermingle [source: Fox]. Unfortunately for all you hard-workers out there, the pheromone that accompanies male body odor that's been baking on the skin for awhile -- androstenone -- is a female repellent.

Even if you take frequent showers topped off with pleasant-smelling cologne, you may not necessarily attract female counterparts. The good news, however, is that researchers report wearing your favorite cologne will make you feel less tense, angry or confused and -- by default -- more fun to be around. Don't reach for synthetic pheromone spray, though, unless you have money to burn. The jury's still out on whether these sprays are effective, although a few titillating studies suggest they may attract women in small measure. Pheromone sprays, and pheromones in general, seem to have the greatest effect when used in close quarters. However, to get to these one-on-one situations, a man must rely on other means of attracting a mate in the first place [source: Fox].

While this may seem like largely anecdotal advice, there's plenty of research to back it up. Unfortunately, there are a lot of variables to contend with that make strong conclusions elusive. Thanks to a healthy measure of free will, humans rely on complex decision-making to determine attractiveness, including how appealing they feel at the moment [source: Fox]. Of course, if you'd really like a boost, dab a bit of grapefruit juice behind your ear lobes. Studies show that when women smell like pink grapefruit, they're perceived to be five years younger than their actual age [source: Weir].